The invention relates to a gripping device having gripping arms which can be moved to and from a gripping position for firmly gripping a tool or workpiece.
A gripping device is disclosed in German Offenlegungsschrift No. 2,647,945 in which the gripping arms, via in each case two toggle levers, are connected in an articulated manner to a wedge block which forms part of the drive for the gripping arms. The wedge block itself is displaced by two levers, each of which in turn interacts with a displaceable pin. This gripping device has a very complicated construction and is also susceptible to trouble as a result of the plurality of parts. Assembling this gripping device is complicated and expensive.
In another known gripping device disclosed in German Patent Specification No. 3,343,765 curved guideways in which the gripping arms are guided are provided for the gripping arms in the housing. They are provided with sliding blocks which engage into a groove of a slide running at right angles to the displacement direction of the gripping arms. With this slide, the gripping arms are displaced into the inoperative position or into the gripping position. The curved guideways and the gripping arms following them require true-to-size production, otherwise the gripping arms will jam in the groove-shaped guides. This gripping device is therefore susceptible to trouble during operation.